IMAGING DEVICE AND A METHOD FOR PRODUCING A THREE-DIMENSIONAL IMAGE OF AN OBJECT

• US 20160007009A1
• Filed: 07/07/2014
• Published: 01/07/2016
• Est. Priority Date: 07/07/2014
• Status: Active Grant

• Current Assignee: Infineon Technologies Dresden GmbH & Co. KG (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Dresden GmbH (Infineon Technologies AG)
• Inventors: Offenberg, Dirk
• Granted Patent: US 10,237,534 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01S 17/86 Combinations of lidar systems with systems other than lidar, radar or sonar, e.g. with direction finders
• CPC Class Codes: G01S 17/894 3D imaging with simultaneous measurement of time-of-flight at a 2D array of receiver pixels, e.g. time-of-flight cameras or flash lidar
• CPC Class Codes: H04N 13/204 using stereoscopic image cameras stereoscopic photography G03B35/00
• CPC Class Codes: H04N 13/207 using a single 2D image sensor
• CPC Class Codes: H04N 13/254 in combination with electromagnetic radiation sources for illuminating objects
• CPC Class Codes: H04N 13/257 Colour aspects

Abstract

An imaging device includes an image sensor circuit including a pixel element. The pixel element is configured to receive during a first receiving time interval electromagnetic waves having a first wavelength, and to receive during a subsequent second receiving time interval electromagnetic waves having a second wavelength. The imaging device includes an image processing circuit configured to produce a color image of the object based on a first pixel image data and a second pixel image data. The first pixel image data is based on the electromagnetic waves having the first wavelength received by the pixel element during the first receiving time interval. The second pixel image data is based on the electromagnetic waves having the second wavelength received by the pixel element during the second receiving time interval.

Claims

1. An imaging device comprising:

an image sensor circuit comprising a pixel element, wherein the pixel element is configured to receive during a first receiving time interval electromagnetic waves having a first wavelength, the electromagnetic waves having the first wavelength emitted by a light emitting device and reflected by an object, and to receive during a subsequent second receiving time interval electromagnetic waves having a second wavelength, the electromagnetic waves having the second wavelength emitted by the light emitting device and reflected by the object; and

an image processing circuit configured to produce a color image of the object based on a first pixel image data and a second pixel image data, wherein the first pixel image data is based on the electromagnetic waves having the first wavelength received by the pixel element during the first receiving time interval, and wherein the second pixel image data is based on the electromagnetic waves having the second wavelength received by the pixel element during the second receiving time interval.

2. The imaging device according to claim 1, further comprising a light emitting device configured to emit during a first emitting time interval the electromagnetic waves having the first wavelength and during a subsequent second emitting time interval the electromagnetic waves having the second wavelength.

3. The imaging device according to claim 1, wherein the electromagnetic waves having the first wavelength comprise visible light of a first color, and wherein the electromagnetic waves having the second wavelength comprise visible light of a second color.

4. The imaging device according to claim 1, wherein the pixel element is configured to receive during the first receiving time interval the electromagnetic waves having the first wavelength and during the subsequent second receiving time interval the electromagnetic waves having the second wavelength at a same electromagnetic wave receiving area of the pixel element.

5. The imaging device according to claim 1, wherein the pixel element comprises an electromagnetic wave receiving area, wherein the electromagnetic wave receiving area defines the smallest unit area used by the image sensor circuit for obtaining the first pixel image data and the second pixel image data.

6. The imaging device according to claim 1, wherein the image sensor circuit comprises a number of pixel elements used for obtaining pixel image data for the produced color image of the object equal to a number of pixels of the produced color image of the object.

7. The imaging device according to claim 1, wherein the pixel element is further configured to receive during a third receiving time interval ambient light reflected by the object, and wherein the image processing circuit is further configured to produce the color image or an additional brightness image of the object based on third pixel image data, wherein the third pixel image data is based on the ambient light reflected by the object and received by the pixel element.

8. The imaging device according to claim 7, wherein the image processing circuit further comprises a circuit configured to produce the color image of the object based on a subtraction of the third pixel image data from the third pixel image data.

9. The imaging device according to claim 1, wherein the image processing circuit is configured to produce the color image based on intensity information of the first pixel image data and intensity information of the second pixel image data.

10. The imaging device according to claim 1, wherein the image processing circuit is configured to produce the color image or an additional three-dimensional image based on distance information of the first pixel image data, wherein the distance information of the first pixel image data is based on a phase delay between the electromagnetic waves having the first wavelength emitted during a first emitting time interval by a light emitting device and the electromagnetic waves having the first wavelength received during the first receiving time interval.

11. The imaging device according to claim 1, wherein the image processing circuit comprises a modulation control circuit configured to provide a modulation control signal to a light emitting device emitting the electromagnetic waves having the first wavelength and the electromagnetic waves having the second wavelength for controlling a modulation of the electromagnetic waves having the first wavelength and the electromagnetic waves having the second wavelength.

12. The imaging device according to claim 1, wherein the image processing circuit comprises a lock-in amplifying circuit configured to obtain intensity information of the first pixel image data based on the first pixel image data and a modulation control signal used for controlling a modulation of the electromagnetic waves having the first wavelength emitted by a light emitting device and the electromagnetic waves having the second wavelength emitted by a light emitting device.

13. The imaging device according to claim 1, wherein the image processing circuit is configured to determine intensity information and distance information of the first pixel image data based on an auto-correlations function.

14. The imaging device according to claim 1, further comprising an infra-red emitting circuit configured to emit during a further emitting time interval infra-red electromagnetic waves, wherein the pixel element is configured to receive during a further receiving time interval infra-red electromagnetic waves emitted by the infra-red emitting circuit and reflected by an object, and wherein the image processing circuit is configured to produce the color image or an additional three-dimensional image based on pixel distance image data, wherein the pixel distance image data is based on the infra-red electromagnetic waves received by the pixel element during the further receiving time interval.

15. The imaging device according to claim 1, wherein the electromagnetic waves having the first wavelength and the electromagnetic waves having the second wavelength are received by the pixel element through a common light path.

16. The imaging device according to claim 15, wherein the common light path is passable to electromagnetic waves of the first wavelength and the electromagnetic waves of the second wavelength during the first receiving time interval and the second receiving time interval.

17. The imaging device according to claim 1, wherein the pixel element is one in an array of pixel elements comprised by the image sensing circuit, wherein the image processing circuit is configured to produce the color image based on first pixel image data and second pixel image data from each pixel element in the array of pixel elements.

18. The imaging device according to claim 17, wherein the image processing circuit is configured to produce a plurality of successive color images of the object based on a plurality of successive first pixel image data and a plurality of successive second pixel image data produced by the array of pixel elements, and wherein the image processing circuit is configured to combine the plurality of successive color images to produce a final color image.

19. A method for producing a color image of an object, the method comprising:

receiving, by a pixel element of an image sensor circuit, during a first receiving time interval electromagnetic waves having a first wavelength, the electromagnetic waves having the first wavelength emitted by a light emitting device and reflected by an object;

receiving, by the pixel element, during a subsequent second receiving time interval electromagnetic waves having a second wavelength, the electromagnetic waves having the second wavelength emitted by the light emitting device and reflected by the object; and

producing, by an image processing circuit, a color image of the object based on a first pixel image data and a second pixel image data, wherein the first pixel image data is based on the electromagnetic waves having the first wavelength received by the pixel element during the first receiving time interval, and wherein the second pixel image data is based on the electromagnetic waves having the second wavelength received by the pixel element during the second receiving time interval.

20. A method for producing a three-dimensional image of an object, the method comprising:

modulating a visible light source external to a time of flight camera to emit modulated electromagnetic waves based on a modulation control signal generated by the time of flight camera;

receiving by the time of flight camera the modulated electromagnetic waves reflected by an object; and

producing a three-dimensional image of the object based on the received modulated electromagnetic waves, wherein the received modulated electromagnetic waves are emitted by the visible light source and reflected by the object.